from django.http import HttpResponseNotFound, JsonResponse, HttpResponseServerError
from django.shortcuts import render
from django.views import View
from apps.contents.utils import get_categories
from apps.goods import models
from apps.goods.models import GoodsVisitCount, GoodsCategory
from apps.goods.utils import get_breadcrumb
from utils.response_code import RETCODE
# Create your views here.
#1.商品列表页
class ListView(View):
    def get(self, request, category_id, page_num):
        #获取三级分类的对象
        try:
            from apps.goods import models
            category = models.GoodsCategory.objects.get(id=category_id)
        except Exception as e:
            return HttpResponseNotFound('商品分类找不见')
            #1.商品分类数据
        from apps.contents.utils import get_categories
        categories = get_categories()
        #2.面包屑组件数据
        from apps.goods.utils import get_breadcrumb
        breadcrumb = get_breadcrumb(category)
        #3.排序
        #3.1.获取sort里面参数的值
        sort = request.GET.get('sort', 'default')
        #3.2.判断排序的字段值
        if sort == 'price':
            sort_filed = 'price'
        elif sort == 'hot':
            sort_filed = '-sales'
        else:
            sort_filed = 'create_time'
        #3.3.根据排序规则 获取category_id对应的所有上架的商品
        from apps.goods.models import SKU
        skus = SKU.objects.filter(category=category, is_launched=True).order_by(sort_filed)
        #4.分页
        #4.1 实例化分页器(分页数据,每页显示的个数) --> 返回每页显示的数据skus
        from django.core.paginator import Paginator
        paginator = Paginator(skus, 5)
        #4.2 告诉分页器当前显示的页数
        try:
            page_skus = paginator.page(page_num)
        except Exception as e:
            return HttpResponseNotFound('当前页数超出范围了')
        #4.3 获取总页数
        total_page = paginator.num_pages
        context = {
            'categories': categories,  # 频道分类
            'breadcrumb': breadcrumb,  # 面包屑导航
            'sort': sort,  # 排序字段
            'category': category,  # 第三级分类
            'page_skus': page_skus,  # 分页后数据
            'total_page': total_page,  # 总页数
            'page_num': page_num,  # 当前页码
        }
        return render(request, 'list.html', context)
#2.热销排行页面
class HotView(View):
    def get(self, request, category_id):
        try:
            from apps.goods.models import SKU
            skus = SKU.objects.filter(category_id=category_id, is_launched=True,).order_by('-sales')[:2]
        except Exception as e:
            return JsonResponse({'code': RETCODE.OK, 'errmsg': '没有当前商品' })
        hot_skus = []
        for sku in skus:
            hot_skus.append({
                'id': sku.id,
                'default_image_url': sku.default_image.url,
                'name': sku.name,
                'price': sku.price
            })
        return JsonResponse({'code':RETCODE.OK, 'errmsg':'OK', 'hot_skus':hot_skus})
#3.详情页
class DetailView(View):
    def get(self, request, sku_id):
        """提供商品详情页"""
        # 获取当前sku的信息
        try:
            sku = models.SKU.objects.get(id=sku_id)
        except models.SKU.DoesNotExist:
            return render(request, '404.html')
        # 查询商品频道分类
        categories = get_categories()
        # 查询面包屑导航
        breadcrumb = get_breadcrumb(sku.category)
        # 构建当前商品的规格键
        sku_specs = sku.specs.order_by('spec_id')
        sku_key = []
        for spec in sku_specs:
            sku_key.append(spec.option.id)
        # 获取当前商品的所有SKU
        skus = sku.spu.sku_set.all()
        # 构建不同规格参数（选项）的sku字典
        spec_sku_map = {}
        for s in skus:
            # 获取sku的规格参数
            s_specs = s.specs.order_by('spec_id')
            # 用于形成规格参数-sku字典的键
            key = []
            for spec in s_specs:
                key.append(spec.option.id)
            # 向规格参数-sku字典添加记录
            spec_sku_map[tuple(key)] = s.id
        # 获取当前商品的规格信息
        goods_specs = sku.spu.specs.order_by('id')
        # 若当前sku的规格信息不完整，则不再继续
        if len(sku_key) < len(goods_specs):
            return
        for index, spec in enumerate(goods_specs):
            # 复制当前sku的规格键
            key = sku_key[:]
            # 该规格的选项
            spec_options = spec.options.all()
            for option in spec_options:
                # 在规格参数sku字典中查找符合当前规格的sku
                key[index] = option.id
                option.sku_id = spec_sku_map.get(tuple(key))
            spec.spec_options = spec_options
        # 渲染页面
        context = {
            'categories': categories,
            'breadcrumb': breadcrumb,
            'sku': sku,
            'specs': goods_specs,
        }
        return render(request, 'detail.html', context)
#4.统计商品访问量
class DetailVisitView(View):
    def post(self, request, category_id):
        try: #获取当前商品
            category = GoodsCategory.objects.get(id=category_id)
        except Exception as e:
            return HttpResponseNotFound("缺少必传参数")
        from datetime import datetime
        today_str = datetime.now().strftime('%Y-%m-%d')
        today_date = datetime.strptime(today_str, '%Y-%m-%d')
        try:
            count_data = category.goodsvisitcount_set.get(date=today_date)
        except:
            count_data = GoodsVisitCount()
        try:
            count_data.count += 1
            count_data.category = category
            count_data.save()
        except Exception as e:
            return HttpResponseServerError("新增失败")
        return JsonResponse({'code':RETCODE.OK, 'errmsg':'OK'})
